1. Technical Field
The present invention relates to a device for detecting at least one variable relating to the movement of a movable body, especially in a machine or an installation.
Such a device can be useful, for example, for the purpose of regulating a motive force or a braking force or a time limit to be provided for the braking of the movable body, etc.
The variable to be detected can be the instantaneous position of the movable body, its speed or its acceleration. Because of the diversity of these variables, the possible nature of the movable body and the atmospheres in which it may be located, it is a necessary precondition to provide several types of instrument.
2. Related Art
Certainly, there are known devices, called "position switches" or "limit switches", which comprise a movement sensor intended, at rest, to be located in the path of the movable body or of an actuating member fastened to the movable body. When the sensor is actuated by the movable body, it in turn actuates a control tappet of a switch.
This type of switch allows only relatively crude synchronised controls.